In this "mixture of history and memoir", Bostonian Christina Thompson, a woman in her 20s who is in Melbourne on a postgraduate scholarship, takes a holiday in New Zealand. In a pub in the Bay of Islands she meets a Maori called Seven, misses her bus back to Auckland, and spends the night with him and his cousins in a nearby house. Next day she accepts an invitation to go with them to Seven's parents' house in Mangonui. Soon he and she are living together in a little shack on the beach.

She returns to work in Melbourne, but after a month with no word from him she phones and invites him to visit. He comes, moves in with her, and within a year they are married. At the end of the book, described as "an unlikely love story", they have three sons and are living in her parental home in Boston.

The book focuses on the 15 years she spent in the Pacific region, and on the interaction of cultures. What makes it puzzling, however, is its impersonality: the lack of detail about the central relationship, and the lack of a strong sense of the Maori husband. He is described, but not realised. We are told often that he is 6ft 2in, strongly built, with long, thick black hair; that he is attractive to women, tranquil, unworried, "cool", and mostly silent. But he is seldom represented speaking or in action.

I kept thinking of Henry James's injunction, "Dramatise! Dramatise!" But in one of the very few moments in the book when Seven speaks, he responds to Christina's account of a dream by saying: "We indigenous people never have those sorts of dreams." "We indigenous people"? This is a response I find it impossible to imagine any Maori making, except tongue-in-cheek. Is the author inventing dialogue to sustain a thesis? Or is Seven giving his wife what he knows she wants to hear? This abstract or illustrative quality is increased by the fact that he is seen as a representative of Polynesia, and even likened to Omai, the young Tahitian brought by Cook to London, where he was paraded as the Noble Savage.

The book opens with New Zealand examples of what anthropologists call "contact encounters". There is Abel Tasman's 1642 attempt at a friendly meeting with Maori and the murder of four of his sailors; Jean de Surville's 1769 encounters with Maori in the north of the country, which began amicably but ended in the theft of one of his boats and his kidnapping of a Maori (who died at sea) and setting fire to 30 houses, by way of revenge; Marion du Fresne, whose five idyllic weeks in 1772 among the "noble savages" of the Bay of Islands ended in his murder and that of a number of his crew. Finally, there is a deadly encounter between Cook and Maori, also in the Bay of Islands, which foreshadowed the circumstances of his murder in Hawaii 10 years later.

The point of all this is not so much the murder, cannibalism and revenge as the misunderstandings on both sides that led to them. But what is their relation to the central narrative? The author represents herself as Europe to her husband's Polynesia; and there is even, perhaps, the suggestion that theirs is a latter-day "contact encounter". But since their interactions are either harmonious or unexplored, it's hard to see why all this rather familiar history is deployed, unless as a hopeful attempt to lend weight to what is otherwise blandly domestic. The impression is of an academic attempting to make something significant of cultural differences that are not creating difficulties; none, anyway, for her Maori husband. Often, as she acknowledges, he seems only to confirm what she has been taught are popular and largely groundless stereo-types about "easygoing" Polynesians.

At times the emphasis on his appearance makes him seem like a trophy daringly brought back to cultured New England from the wilds of the South Pacific. To one who lives in what is frequently referred to as the world's largest Polynesian city, where intermarriage is commonplace, this aspect of the book seems at the very least naive.

But there is another undertone that becomes specific only in later chapters. The author is from a sophisticated, affluent family; Seven is a minimally educated manual worker. They move about as she gets postgrad grants, editing jobs, research work that can be combined with motherhood. He finds work, but often with difficulty, and it is poorly paid. It is when Seven takes a job as a door-to-door salesman that "for the first time in our marriage I despaired . . . this forced me to acknowledge the issue of class. Of course I had always known it was there between us, but I never paid it much attention . . . it was easier for me to think of the differences between Pakeha [New Zealanders of predominantly European ancestry] and Maori than about those between the privileged and the poor. But there were moments - days when I would come home from the university and find Seven and Kura [his sister] on the floor watching monster trucks on TV - when I would look at them and think, you people." This brief moment seems to cut closer to a world of difference than a lot of the book's lucubrations on Europe and Polynesia.

In the end, their money problems are solved by returning to Boston and her parents: "My mother could cook, I could clean, my father could pay the bills, Seven could do the heavy lifting." The tone is light; but in a book full of unsatisfactory analogies, we might see ourselves here on the brink of another kind of "contact encounter" - that between the generations.